1. Field of the Invention
The present invention relates to a self-moving robot, and more particularly to a system and method for automatically returning a self-moving robot to a charger wherein the self-moving robot can quickly and accurately return to the charger through infrared image information of an infrared module provided on the charger, which has been input from a camera module provided on the self-moving robot.
2. Description of the Related Art
Robots have been developed for industrial purposes and used as part of factory automation. Robots also have been used, in place of human beings, to collect information in extreme environments that human beings cannot access. Robot technologies have been rapidly developed as applied to the most advanced space development industries. Recently, even human-friendly household robots have been developed. A typical example of the human-friendly household robot is a self-moving cleaning robot.
The self-moving cleaning robot is a device that sucks up dust or other foreign particles while automatically moving within a specific cleaning area as in a residence or office. In addition to the components of a general vacuum cleaner that sucks up dust or other foreign particles, the self-moving cleaning robot includes a propelling unit for moving the robot, a number of detection sensors for detecting a variety of obstacles so that the robot moves without colliding with obstacles in the cleaning area, a battery for supplying power to each component of the robot, and a microprocessor for controlling each component of the robot.
Using the detection sensors, the cleaning robot determines distances to a variety of obstacles such as furniture and walls in the cleaning area, and cleans the cleaning area while moving without colliding with obstacles using the determined information.
Recently, a self-moving cleaning robot that has a camera module to detect positions of a cleaning area in order to clean the cleaning area without omitting any part thereof has been introduced.
This self-moving robot can not only detect its own position but also obtain accurate information of the cleaning area through surrounding images captured by the camera module, so that it can more accurately clean the cleaning area without omitting any part thereof.
On the other hand, as the self-moving cleaning robot is driven by the battery as described above, it has an automatic battery charging function for user convenience. Through the automatic charging function, the self-moving robot detects its battery level, and, if the battery level is lower than a reference level, the self-moving robot automatically returns to a charger provided at a specific position in the cleaning area and resumes the cleaning operation after the battery is fully charged by the charger.
In the conventional method for automatically returning the self-moving cleaning robot to the charger, the self-moving robot determines the position of the charger by detecting infrared light emitted from an infrared transmitter provided on the charger using an infrared sensor provided on the self-moving robot in order to return to the charger.
However, in the conventional method, it takes a long time for the infrared sensor provided on the self-moving robot to detect infrared light emitted from the infrared transmitter since the infrared sensor not only has a narrower light receiving range but also cannot detect the infrared signal when the self-moving robot is more than a specific distance away from the infrared transmitter. If it takes a long time to detect the infrared light emitted from the infrared transmitter, the battery may be discharged and the self-moving robot may stop on the way back to the charger.